Certain pyridyloxy-phenoxyalkane carboxylic acids and derivatives thereof are disclosed in U.S. Pat. No. 4,115,102 to have a strong selective herbicidal activity toward gramineous plants but to affect broad-leafed plants to only a slight extent. Said patent further discloses that such compounds can be applied to kill gramineous weeds on farms where gramineous crops are cultivated if they are applied in small dosage (5-20 g/a) and the plants have grown to some degree.
Belgian Pat. No. 862,325, on the hand, discloses derivatives of pyridyloxy-phenoxyalkane carboxylic acids having herbicidal and phytoregulatory action to selectivity control plants harmful to crops and to selectively regulate the growth of plants (including gramineous plants and grains, and dicotyledons).
However, neither patent discloses any other biological action of such compounds. In particular, neither patent discloses the use of such compounds to increase the sugar content of plants such as sugarcane (Saccharum officinerum) or sorghum (Sorghum vulgare). Increased sugar content, of course, increases the value of such plants.